Fix mTLS cert to include CA cert

[EnigmaCurry]

On GrapheneOS (and possibly iPad) the mTLS cert generated by step-ca does not import. This was tested by @mcmikemn to be due to the fact that the CA cert is not included. Even though its the server's job to validate the client cert, graphene seems to need it anyway.

d.rymcg.tech/step-ca/Makefile

Lines 53 to 55 in 7352447

	.PHONY: cert # Create certificate
	cert:
	@CN=$$(${BIN}/ask_echo "Enter the subject (CN) to be certified, a domain name, or a client name"); ${STEP} ca certificate "$${CN}" "certs/$${CN}.crt" "certs/$${CN}.key" --not-after "$$(${BIN}/dotenv -f ${ENV_FILE} get STEP_CA_AUTHORITY_CLAIMS_DEFAULT_TLS_CERT_DURATION)" && ${STEP} certificate p12 "certs/$${CN}.p12" "certs/$${CN}.crt" "certs/$${CN}.key" && ${STEP} certificate inspect "certs/$${CN}.crt"

mike says

step ca root root.crt
cat client.crt root.crt > combined.crt
step certificate p12 combined.crt client.key newclient.p12